Electronic component

ABSTRACT

An element body includes a first principal surface and a second principal surface opposing each other in a first direction. A first terminal electrode is disposed on the first principal surface side of the element body. A second terminal electrode is disposed on the second principal surface side of the element body. The first terminal electrode includes a first sintered metal layer formed on the first principal surface; and a first plating layer formed on the first sintered metal layer and including base metal. The second terminal electrode includes a second sintered metal layer formed on the second principal surface, a second plating layer formed on the second sintered metal layer and including base metal, and a solder layer formed on the second plating layer and including Sn and a metal having a higher melting point than the melting point of Sn.

TECHNICAL FIELD

The present invention relates to an electronic component.

BACKGROUND

Japanese Unexamined Patent Publication No. H10-022160 discloses anelectronic component including an element body having a first principalsurface and a second principal surface opposing each other in a firstdirection, a first terminal electrode disposed on a first principalsurface side of the element body, and a second terminal electrodedisposed on a second principal surface side of the element body. Thefirst terminal electrode is connected to an electrode disposed on anelectronic device (for example, circuit board or electronic component)by wire bonding. The first terminal electrode is connected to theelectrode disposed on the electronic device through wire. The secondterminal electrode is directly connected to another electrode disposedon the electronic device.

SUMMARY

An object of one aspect of the present invention is to provide anelectronic component to which wire bonding mounting using wire includingbase metal (for example, Al or Cu) is possible on the first principalsurface side, and to which solder mounting is possible on the secondprincipal surface side.

An electronic component according to one aspect of the present inventionincludes an element body having a first principal surface and a secondprincipal surface opposing each other in a first direction, a firstterminal electrode disposed on the first principal surface side of theelement body, and a second terminal electrode disposed on the secondprincipal surface side of the element body. The first terminal electrodeincludes a first sintered metal layer formed on the first principalsurface and a first plating layer formed on the first sintered metallayer. The first plating layer includes the base metal. The secondterminal electrode includes a second sintered metal layer formed on thesecond principal surface, a second plating layer formed on the secondsintered metal layer, and a solder layer formed on the second platinglayer. The second plating layer includes the base metal. The solderlayer includes Sn, and a metal having a higher melting point than themelting point of Sn.

In the electronic component according to the one aspect, since the firstterminal electrode disposed on the first principal surface side of theelement body includes the first plating layer, the wire bonding mountingusing the wire including the base metal is possible on the firstprincipal surface side. The wire bonding mounting using the wireincluding the base metal is less expensive than the wire bondingmounting using wire including Au.

In the electronic component according to the one aspect, since thesecond terminal electrode disposed on the second principal surface sideof the element body includes the solder layer, the solder mounting ispossible on the second principal surface side. Since the second terminalelectrode includes the second plating layer, bonding strength betweenthe second plating layer and the solder layer is improved.

In the electronic component according to the one aspect, the firstplating layer is formed on the first sintered metal layer formed on thefirst principal surface of the element body, and the second platinglayer is formed on the second sintered metal layer formed on the secondprincipal surface of the element body. For this reason, when the firstplating layer is formed, infiltration of a plating solution into theelement body is suppressed by the first sintered metal layer, and whenthe second plating layer is formed, infiltration of a plating solutioninto the element body is suppressed by the second sintered metal layer.The infiltration of the plating solution may deteriorate electricalcharacteristics of the electronic component. Therefore, the infiltrationof the plating solution is suppressed, so that deterioration of theelectrical characteristics of the electronic component is suppressed.

The first plating layer may be a Ni plating layer or a Cu plating layer.In this case, the wire including Al or Cu is easily bonded to the firstplating layer.

A depression may be formed in an inner area when viewed from a directionperpendicular to the second principal surface, on an electrode structureincluding the second sintered metal layer and the second plating layer.In this case, the solder layer may be formed convexly on the depression.In this embodiment, an amount of solder configuring the solder layer isgreater in comparison with, for example, a configuration in which thedepression is not formed in the electrode structure. For this reason,when the electronic component is solder-mounted to the electronic deviceon the second principal surface side, generation of a void in the solderis suppressed. As a result, bonding strength between the electroniccomponent and the electronic device is improved.

The metal having the higher melting point than the melting point of Snmay be Sb. The solder layer including Sb as the metal having the highermelting point than the melting point of Sn is less expensive than thesolder layer including a precious metal as the metal having the highermelting point than the melting point of Sn. For this reason, cost of theelectronic component is reduced.

The second plating layer may be a Ni plating layer. In this case, theremay be an area in which an alloy of Ni and Sn exists, between the secondplating layer and the solder layer. Because of the area in which thealloy of Ni and Sn exists, bonding strength between the Ni plating layerand the solder layer is improved.

The electronic component according to the one aspect may further includea plurality of internal electrodes. In this case, the electroniccomponent of this embodiment may include the following configuration.The plurality of internal electrodes is arranged at equal intervals in asecond direction perpendicular to the first direction to oppose eachother, inside the element body. In this case, the plurality of internalelectrodes includes a plurality of first internal electrodes connectedto the first terminal electrode and not connected to the second terminalelectrode, a plurality of second internal electrodes connected to thesecond terminal electrode and not connected to the first terminalelectrode, a plurality of third internal electrodes not connected to atleast the second terminal electrode, and a plurality of fourth internalelectrodes not connected to at least the first terminal electrode. Theelement body includes a plurality of first areas, each of which ispositioned between each of the first internal electrodes and each of thesecond internal electrodes opposing each other, and a plurality ofsecond areas, each of which is positioned between the first internalelectrodes opposing each other via each of the third internal electrodesand between the second internal electrodes opposing each other via eachof the fourth internal electrodes. Each of the first areas and each ofthe second areas are positioned alternately in the second direction.

In this embodiment, the electronic component functions as a multilayercapacitor.

The first internal electrodes connected to the first terminal electrodeand the second internal electrodes connected to the second terminalelectrode have different polarities from each other. The first areas,each of which is positioned between the first and second internalelectrodes opposing each other, generates capacitance. The firstinternal electrodes have the same polarity to each other. The thirdinternal electrodes not connected to the second terminal electrode donot have a different polarity from a polarity of the first internalelectrodes at least. The second internal electrodes have the samepolarity to each other. The fourth internal electrodes not connected tothe first terminal electrode do not have a different polarity from apolarity of the second internal electrodes at least. Therefore, each ofthe second areas positioned between the first internal electrodesopposing each other via each of the third internal electrodes, and eachof the second areas positioned between the second internal electrodesopposing each other via each of the fourth internal electrodes do notgenerate capacitance.

The element body includes an internal electrode disposition area inwhich the plurality of internal electrodes is disposed, and a pair ofinternal electrode non-disposition areas in which the plurality ofinternal electrodes is not disposed. The pair of internal electrodenon-disposition areas sandwiches the internal electrode disposition areain the second direction. The internal electrode disposition areaincludes the plurality of first areas that generates capacitance, andthe plurality of second areas that does not generate capacitance.Therefore, in the multilayer capacitor of this embodiment, a desiredcapacitance is secured by the plurality of first areas.

The second areas that do not generate capacitance are included in theinternal electrode disposition area. For this reason, in the multilayercapacitor of this embodiment, the internal electrode disposition area iswider, and the internal electrode non-disposition area is narrower, incomparison with the following multilayer capacitor to be compared. Inthe multilayer capacitor to be compared, the internal electrodes havingdifferent polarities are disposed alternately, and size and capacitanceof the element body are the same as those of the multilayer capacitor ofthis embodiment.

In the multilayer capacitor, in general, the element body is configuredas a sintered body of a dielectric ceramic material, and each of theinternal electrodes is configured as a sintered body of a metalmaterial. A degree of sintering of the dielectric ceramic material inthe internal electrode disposition area and a degree of sintering of thedielectric ceramic material in the internal electrode non-dispositionarea are different from each other due to presence/absence of the metalmaterial to be the internal electrodes. For example, the degree ofsintering of the dielectric ceramic material in the internal electrodenon-disposition area is lower than the degree of sintering of thedielectric ceramic material in the internal electrode disposition area.In a case in which the degree of sintering of the dielectric ceramicmaterial in the internal electrode disposition area and the degree ofsintering of the dielectric ceramic material in the internal electrodenon-disposition area are different from each other, a crack may begenerated in the element body.

In the internal electrode disposition area, all internal electrodes arearranged at equal intervals in the second direction. For this reason, inthe internal electrode disposition area, the degree of sintering of thedielectric ceramic is substantially uniform. In the multilayer capacitorof this embodiment, the internal electrode disposition area is widerthan that of the multilayer capacitor to be compared, that is, the areais wider in which the degree of sintering of the dielectric ceramic issubstantially uniform, so that the degree of sintering of the dielectricceramic in the entire of the element body is stabilized. As a result,generation of the crack in the element body is suppressed.

In a case in which voltage is applied to the multilayer capacitor,mechanical strain of a size depending on the applied voltage isgenerated due to electrostrictive effect in the element body. Sincestress is generated in the element body by the mechanical strain due tothe electrostrictive effect, a crack may be generated in the elementbody.

Although the mechanical strain due to the electrostrictive effect isgenerated in the first areas, the mechanical strain due to theelectrostrictive effect is not generated in the second areas. The firstareas and the second areas are positioned alternately in the seconddirection. Therefore, in the multilayer capacitor of this embodiment, incomparison with the multilayer capacitor in which the internal electrodedisposition area does not include the second areas, the areas in whichthe mechanical strain due to the electrostrictive effect is generatedare distributed in the internal electrode disposition area. Thus,concentration of the stress is suppressed that is generated by themechanical strain due to the electrostrictive effect. As a result,generation of the crack in the element body is suppressed.

From these things, in the multilayer capacitor of this embodiment,generation of the crack is suppressed while the desired capacitance issecured.

The electronic component according to the one aspect may further includea plurality of first internal electrode groups, a plurality of secondinternal electrode groups, a plurality of third internal electrodegroups, and a plurality of fourth internal electrode groups. In thiscase, the electronic component of this embodiment may include thefollowing configuration. Each of the first internal electrode groupsincludes a first number of the first internal electrodes. The firstnumber of the first internal electrodes are connected to the firstterminal electrode, and are arranged in the second directionperpendicular to the first direction inside the element body. Each ofthe second internal electrode groups includes the first number of thesecond internal electrodes. The first number of the second internalelectrodes are connected to the second terminal electrode, and arearranged in the second direction inside the element body. Each of thethird internal electrode groups includes a second number of the firstinternal electrodes. The second number of the first internal electrodesare connected to the first terminal electrode, and are arranged in thesecond direction inside the element body. Each of the fourth internalelectrode groups includes the second number of the second internalelectrodes. The second number of the second internal electrode areconnected to the second terminal electrode, and are arranged in thesecond direction inside the element body. The first number and thesecond number are integers of two or greater that are different fromeach other. The element body includes an inner portion, and a pair ofouter portions positioned to sandwich the inner portion in the seconddirection. An interval in the second direction between first internalelectrodes included in each of the first internal electrode groups, aninterval in the second direction between the second internal electrodesincluded in each of the second internal electrode groups, an interval inthe second direction between each of the first internal electrodesincluded in each of the first internal electrode groups and each of thesecond internal electrodes included in each of the second internalelectrode groups, an interval in the second direction between the firstinternal electrodes included in each of the third internal electrodegroups, an interval in the second direction between the second internalelectrodes included in each of the fourth internal electrode groups, andan interval in the second direction between each of the first internalelectrodes included in each of the third internal electrode groups andeach of the second internal electrodes included in each of the fourthinternal electrode groups are equivalent to each other. Each of thefirst internal electrode groups and each of the second internalelectrode groups are positioned in the pair of outer portions, and arearranged alternately in the second direction in such a manner that onefirst internal electrode of the first number of the first internalelectrodes included in each of the first internal electrode groups andone second internal electrode of the first number of the second internalelectrodes included in each of the second internal electrode groupsoppose each other in the second direction. Each of the third internalelectrode groups and each of the fourth internal electrode groups arepositioned in the inner portion, and are arranged alternately in thesecond direction in such a manner that one first internal electrode ofthe second number of the first internal electrodes included in each ofthe third internal electrode groups and one second internal electrode ofthe second number of second internal electrodes included in each of thefourth internal electrode groups oppose each other in the seconddirection.

In this embodiment, the electronic component functions as a multilayercapacitor.

The plurality of first internal electrode groups and the plurality ofsecond internal electrode groups are arranged alternately in the seconddirection. The one first internal electrode of the first number of thefirst internal electrodes included in each of the first internalelectrode groups and the one second internal electrode of the firstnumber of the second internal electrodes included in each of the secondinternal electrode groups oppose each other in the second direction.Thus, a plurality of areas that generates capacitance is disposed ineach of the outer portions.

Since the first number of the first internal electrodes included in eachof the first internal electrode groups all have the same polarity, ineach of the first internal electrode groups, an area between the firstinternal electrodes respectively positioned at both ends in the seconddirection of the first number of the first internal electrodes does notgenerate capacitance. Since the first number of the second internalelectrodes included in each of the second internal electrode groups allhave the same polarity, in each of the second internal electrode groups,an area between the second internal electrodes respectively positionedat both ends in the second direction of the first number of the secondinternal electrodes does not generate capacitance. For this reason, ineach of the outer portions of the element body, the areas that generatecapacitance and the areas that do not generate capacitance arepositioned alternately in the second direction.

The plurality of third internal electrode groups and the plurality offourth internal electrode groups are arranged alternately in the seconddirection. The one first internal electrode of the second number of thefirst internal electrodes included in each of the third internalelectrode groups and the one second internal electrode of the secondnumber of the second internal electrodes included in each of the fourthinternal electrode groups oppose each other in the second direction.Thus, a plurality of areas that generates capacitance is disposed in theinner portion.

Since the second number of the first internal electrodes included ineach of the third internal electrode groups all have the same polarity,in each of the third internal electrode groups, an area between thefirst internal electrodes respectively positioned at both ends in thesecond direction of the second number of the first internal electrodesdoes not generate capacitance. Since the second number of the secondinternal electrodes included in each of the fourth internal electrodegroups all have the same polarity, in each of the fourth internalelectrode group, an area between the second internal electrodesrespectively positioned at both ends in the second direction of thesecond number of the first internal electrodes does not generatecapacitance. For this reason, in the inner portion of the element body,the areas that generate capacitance and the areas that do not generatethe capacitance are positioned alternately in the second direction.

The element body includes the internal electrode disposition area inwhich the plurality of first-fourth internal electrode groups aredisposed, and the pair of internal electrode non-disposition areas inwhich the plurality of first-fourth internal electrode groups are notdisposed. The pair of internal electrode non-disposition areassandwiches the internal electrode disposition area in the seconddirection. The internal electrode disposition area includes theplurality of areas that generates capacitance, and the plurality ofareas that does not generate capacitance. Therefore, in the multilayercapacitor of this embodiment, the desired capacitance is secured by theplurality of areas that generates capacitance.

The plurality of areas that does not generate capacitance is included inthe internal electrode disposition area. For this reason, in themultilayer capacitor of this embodiment, the internal electrodedisposition area is wider, and the internal electrode non-dispositionarea is narrower, in comparison with the following multilayer capacitorto be compared. In the multilayer capacitor to be compared, the internalelectrodes having different polarities are disposed alternately, andsize and capacitance of the element body are the same as those of themultilayer capacitor of this embodiment.

In the internal electrode disposition area, all internal electrodes arearranged at equal intervals in the second direction. For this reason, inthe internal electrode disposition area, the degree of sintering of thedielectric ceramic is substantially uniform. In the multilayer capacitorof this embodiment, the internal electrode disposition area is widerthan that of the multilayer capacitor to be compared, that is, the areais wider in which the degree of sintering of the dielectric ceramic issubstantially uniform, so that the degree of sintering of the dielectricceramic in the entire of the element body is stabilized. As a result,generation of the crack in the element body is suppressed.

From these things, in the multilayer capacitor of this embodiment,generation of the crack is suppressed while the desired capacitance issecured. In this case, the first number may be greater than the secondnumber.

In a case in which the first number is greater than the second number,the number of the first internal electrodes included in the firstinternal electrode groups positioned in the outer portions, and thenumber of the second internal electrodes included in the second internalelectrode groups also positioned in the outer portions are greater thanthe number of the first internal electrodes included in the thirdinternal electrode groups positioned in the inner portion, and thenumber of second internal electrodes included in the fourth internalelectrode group also positioned in the inner portion. For this reason,in a case in which a crack is generated in the outer portions, the crackhardly reaches the first and second internal electrodes that havedifferent polarities from each other and contribute capacitance.

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingswhich are given by way of illustration only, and thus are not to beconsidered as limiting the present invention.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating a multilayer ceramic capacitoraccording to an embodiment.

FIG. 2 is a diagram for describing a cross-sectional configuration ofthe multilayer ceramic capacitor according to the embodiment.

FIG. 3 is a diagram for describing a cross-sectional configuration ofthe multilayer ceramic capacitor according to the embodiment.

FIG. 4 is a diagram for describing a cross-sectional configuration ofthe multilayer ceramic capacitor according to the embodiment.

FIG. 5 is a diagram for describing a cross-sectional configuration ofthe multilayer ceramic capacitor according to the embodiment.

FIG. 6 is a diagram for describing a cross-sectional configuration of afirst terminal electrode.

FIG. 7 is a diagram for describing a cross-sectional configuration of asecond terminal electrode.

FIG. 8 is a diagram for describing a configuration of the secondterminal electrode.

FIG. 9 is a diagram for describing mounting structure of the multilayerceramic capacitor according to the embodiment.

FIG. 10 is a diagram for describing a cross-sectional configuration of amultilayer ceramic capacitor according to a modification example of theembodiment.

FIG. 11 is a diagram for describing a cross-sectional configuration ofthe multilayer ceramic capacitor according to the modification exampleof the embodiment.

DETAILED DESCRIPTION

Hereinafter, an embodiment of the present invention is described indetail with reference to accompanying drawings. Incidentally, in thedescription, the same reference numerals are used for the samecomponents or components having the same function, and redundantdescriptions are omitted.

First, a configuration is described of a multilayer ceramic capacitor C1according to the embodiment, with reference to FIG. 1 to FIG. 5. FIG. 1is a perspective view illustrating a multilayer ceramic capacitoraccording to the embodiment. FIG. 2 to FIG. 5 are diagrams fordescribing a cross-sectional configuration of the multilayer ceramiccapacitor according to the embodiment. In the embodiment, the multilayerceramic capacitor C1 is described as an example of an electroniccomponent.

As illustrated in FIG. 1 to FIG. 5, the multilayer ceramic capacitor C1includes an element body 3, a first terminal electrode 5 and a secondterminal electrode 6 disposed on an outer surface of the element body 3,and a plurality of internal electrodes 7, 8, 9, 10 disposed in theelement body 3. The first terminal electrode 5 and the second terminalelectrode 6 are separated.

The element body 3 has a rectangular parallelepiped shape. The elementbody 3 has a first principal surface 3 a and a second principal surface3 b opposing each other, a first side surface 3 c and a second sidesurface 3 d opposing each other, and a third side surface 3 e and afourth side surface 3 f opposing each other, as outer surfaces of theelement body 3. The rectangular parallelepiped shape includes a shape ofa rectangular parallelepiped in which corner portions and ridge portionsare chamfered, and a shape of a rectangular parallelepiped in whichcorner portions and ridge portions are rounded.

A length T of the element body 3 in a direction (second direction D2) inwhich the first side surface 3 c and the second side surface 3 d opposeeach other is greater than a length L of the element body 3 in adirection (first direction D1) in which the first principal surface 3 aand the second principal surface 3 b oppose each other. The length T ofthe element body 3 is equal to or less than a length W of the elementbody 3 in a direction (third direction D3) in which the third sidesurface 3 e and the fourth side surface 3 f oppose each other.

The first side surface 3 c and the second side surface 3 d extend in thefirst direction D1 to connect between the first principal surface 3 aand the second principal surface 3 b. The first side surface 3 c and thesecond side surface 3 d extend also in the third direction D3. The thirdside surface 3 e and the fourth side surface 3 f extend in the firstdirection D1 to connect between the first principal surface 3 a and thesecond principal surface 3 b. The third side surface 3 e and the fourthside surface 3 f extend also in the second direction D2.

The element body 3 is configured by stacking a plurality of dielectriclayers in the direction (second direction D2) in which the first sidesurface 3 c and the second side surface 3 d oppose each other. In theelement body 3, the direction in which the plurality of dielectriclayers is stacked coincides with the second direction D2. Each of thedielectric layers is configured from, for example, a sintered body of aceramic green sheet including a dielectric material (dielectric ceramicmaterial such as BaTiO₃-based, Ba(Ti, Zr)O₃-based, or (Ba,Ca)TiO₃-based). In the actual element body 3, the dielectric layers areintegrated so that the boundary is not visible between the dielectriclayers.

The element body 3 includes an inner layer portion 11 and a pair ofouter layer portions 12. In the inner layer portion 11, a plurality ofinternal electrodes 7, 8, 9, 10 is positioned. The pair of outer layerportions 12 is positioned to sandwich the inner layer portion 11 in thesecond direction D2. In the pair of outer layer portions 12, theplurality of internal electrodes 7, 8, 9, 10 is not positioned. In theembodiment, in the second direction D2, a ratio of the length of each ofthe outer layer portions 12 to the length T of the element body 3 is0.05-0.2 (5-20%).

The first terminal electrode 5 is disposed on the first principalsurface 3 a side. The first terminal electrode 5 is formed to cover thefirst principal surface 3 a, an edge portion of the first side surface 3c, an edge portion of the second side surface 3 d, an edge portion ofthe third side surface 3 e, and an edge portion of the fourth sidesurface 3 f. The first terminal electrode 5 includes an electrodeportion positioned on the first principal surface 3 a, an electrodeportion positioned on a portion of the first side surface 3 c, anelectrode portion positioned on a portion of the second side surface 3d, an electrode portion positioned on a portion of the third sidesurface 3 e, and an electrode portion positioned on a portion of thefourth side surface 3 f.

The second terminal electrode 6 is disposed on the second principalsurface 3 b side. The second terminal electrode 6 is formed to cover thesecond principal surface 3 b, an edge portion of the first side surface3 c, an edge portion of the second side surface 3 d, an edge portion ofthe third side surface 3 e, and an edge portion of the fourth sidesurface 3 f. The second terminal electrode 6 includes an electrodeportion positioned on the second principal surface 3 b, an electrodeportion positioned on a portion of the first side surface 3 c, anelectrode portion positioned on a portion of the second side surface 3d, an electrode portion positioned on a portion of the third sidesurface 3 e, and an electrode portion positioned on a portion of thefourth side surface 3 f.

The first terminal electrode 5 includes a first sintered metal layer 51and a first plating layer 53. The first plating layer 53 is theoutermost layer of the first terminal electrode 5.

The first sintered metal layer 51 is formed on the first principalsurface 3 a, the edge portion of the first side surface 3 c, the edgeportion of the second side surface 3 d, the edge portion of the thirdside surface 3 e, and the edge portion of the fourth side surface 3 fThe first sintered metal layer 51 is formed by, for example, applyingconductive paste to the outer surface of the element body 3, andsintering the applied conductive paste. The first sintered metal layer51 is a layer formed by sintering a metal component (metal powder)included in the conductive paste. The conductive paste is applied byusing a printing method, for example.

In the embodiment, the first sintered metal layer 51 is a sintered metallayer including base metal. Specifically, the first sintered metal layer51 is a sintered metal layer including Cu. The first sintered metallayer 51 may be a sintered metal layer including Ni. Thus, the firstsintered metal layer 51 includes the base metal (such as Cu or Ni). Inthe conductive paste, for example, metal powder including the basemetal, a glass component, an organic binder, and an organic solvent aremixed.

The first plating layer 53 is formed on the first sintered metal layer51, and includes the base metal. The first plating layer 53 is formed byusing a plating method. The first plating layer 53 is disposed on thefirst sintered metal layer 51. In the embodiment, the first platinglayer 53 is a Ni plating layer formed by Ni plating on the firstsintered metal layer 51. The first plating layer 53 may be a Cu platinglayer. Thus, the first plating layer 53 includes Ni or Cu as the basemetal.

In a first electrode structure including the first sintered metal layer51 and the first plating layer 53, as illustrated in FIG. 6, adepression is formed in an inner area when viewed from a directionperpendicular to the first principal surface 3 a. Regarding a thicknessof the first electrode structure, a thickness T_(1A) of an inner portionwhen viewed from the direction perpendicular to the first principalsurface 3 a is less than a thickness T_(1B) of an outer portion whenviewed from the direction perpendicular to the first principal surface 3a. In FIG. 6, illustration of the plurality of internal electrodes 7, 8,9, 10 is omitted.

The minimum thickness of the first sintered metal layer 51 in the aboveinner portion of the first electrode structure is, for example, 1-20 μm,and is preferably 5-15 μm. The maximum thickness of the first sinteredmetal layer 51 in the above outer portion of the first electrodestructure is, for example, 10-30 and is preferably 16-25 μm. Thethickness of the first plating layer 53 in the above inner portion ofthe first electrode structure is, for example, 2-5 μm. The thickness ofthe first plating layer 53 in the above outer portion of the firstelectrode structure is, for example, 2-5 μm.

The second terminal electrode 6 includes a second sintered metal layer61, a second plating layer 63, and a solder layer 65. The solder layer65 is the outermost layer of the second terminal electrode 6.

The second sintered metal layer 61 is formed on the second principalsurface 3 b, the edge portion of the first side surface 3 c, the edgeportion of the second side surface 3 d, the edge portion of the thirdside surface 3 e, and the edge portion of the fourth side surface 3 f.The second sintered metal layer 61, similarly to the first sinteredmetal layer 51, is formed by, for example, applying the conductive pasteto the outer surface of the element body 3, and sintering the appliedconductive paste. The second sintered metal layer 61 is also a layerformed by sintering the metal component (metal powder) included in theconductive paste. The conductive paste is applied by using a printingmethod, for example.

In the embodiment, the second sintered metal layer 61 is also thesintered metal layer including the base metal. Specifically, the secondsintered metal layer 61 is a sintered metal layer including Cu. Thesecond sintered metal layer 61 may be the sintered metal layer includingNi. Thus, the second sintered metal layer 61 includes the base metal(such as Cu or Ni). In the conductive paste, for example, metal powderincluding the base metal, a glass component, an organic binder, and anorganic solvent are mixed.

The second plating layer 63 is formed on the second sintered metal layer61, and includes the base metal. The second plating layer 63, similarlyto the first plating layer 53, is formed by using a plating method. Thesecond plating layer 63 is disposed on the second sintered metal layer61. In the embodiment, the second plating layer 63 is a Ni plating layerformed by Ni plating on the second sintered metal layer 61. The secondplating layer 63 may be a Cu plating layer.

In a second electrode structure including the second sintered metallayer 61 and the second plating layer 63, as illustrated in FIG. 7, adepression is formed in an inner area when viewed from a directionperpendicular to the second principal surface 3 b. Regarding a thicknessof the second electrode structure, a thickness T_(2A) of an innerportion when viewed from the direction perpendicular to the secondprincipal surface 3 b is less than a thickness T_(2B) of an outerportion when viewed from the direction perpendicular to the secondprincipal surface 3 b. In FIG. 7, illustration of the plurality ofinternal electrodes 7, 8, 9, 10 is omitted.

The minimum thickness of the second sintered metal layer 61 in the aboveinner portion of the second electrode structure is, for example, 13 μm.The maximum thickness of the second sintered metal layer 61 in the aboveouter portion of the second electrode structure is, for example, 26 μm.The thickness of the second plating layer 63 in the above inner portionof the second electrode structure is for example, 1-4 μm. The thicknessof the second plating layer 63 in the above outer portion of the secondelectrode structure is, for example, 1-4 μm.

The solder layer 65 is formed on the second plating layer 63, andincludes Sn and a metal having a higher melting point than the meltingpoint of Sn. In the embodiment, the solder layer 65 includes Sb as themetal having the higher melting point than the melting point of Sn. Thesolder layer 65 includes a Sn—Sb-based solder alloy. The solder layer 65may include a precious metal (for example, Ag) as the metal having thehigher melting point than the melting point of Sn.

The solder layer 65 is formed by using a reflow method. In the reflowmethod, solder paste is applied on the second plating layer 63, and theapplied solder paste is heated. Thus, the solder paste is melted. Afterthat, the melted solder paste is cooled, and the solder paste issolidified. Thus, the solder layer 65 is formed. The solder paste isapplied on an intended position by using a printing method, for example.The solder paste includes Sn, a metal having the higher melting pointthan the melting point of Sn, and flux.

The solder layer 65 is formed convexly on the depression of the secondelectrode structure. The average thickness of the solder layer 65 is,for example, 20-30 μm. The maximum thickness of the solder layer 65 is,for example, 30-80 μm. The maximum thickness from a virtual plane PLbeing in contact with a position to be the maximum thickness in theabove outer portion of the second electrode structure to a surface ofthe solder layer 65 is, for example, 10-50 μm.

In the embodiment, there is an area 67 in which an alloy of Ni and Sn isincluded, on the second electrode structure. The area 67 exists betweenthe second plating layer 63 and the solder layer 65. The area 67 isformed by alloying Ni included in the second plating layer 63 and Snincluded in the solder paste together when the solder paste applied onthe second plating layer 63 is heated. The thickness of the area 67 is,for example, 0.5-2 μm.

A peripheral portion of the area 67 is exposed from the solder layer 65,as illustrated in FIG. 8. When viewed from the direction perpendicularto the second principal surface 3 b, the peripheral portion of the area67 is positioned to surround the solder layer 65. The solder layer 65 isdisposed on the second plating layer 63 via the area 67.

One end of each of the internal electrodes 7 is exposed to the firstprincipal surface 3 a of the element body 3. Each of the internalelectrodes 7 is connected to the first terminal electrode 5. The otherend of each of the internal electrodes 7 is positioned in the elementbody 3, and is not exposed to the second principal surface 3 b. Each ofthe internal electrodes 7 is not connected to the second terminalelectrode 6.

One end of each of the internal electrodes 9 is exposed to the secondprincipal surface 3 b of the element body 3. Each of the internalelectrodes 9 is connected to the second terminal electrode 6. The otherend of each of the internal electrodes 9 is positioned in the elementbody 3, and is not exposed to the first principal surface 3 a. Each ofthe internal electrodes 9 is not connected to the first terminalelectrode 5.

One end of each of the internal electrodes 8 is exposed to the firstprincipal surface 3 a of the element body 3. Each of the internalelectrodes 8 is connected to the first terminal electrode 5. The otherend of each of the internal electrodes 8 is positioned in the elementbody 3, and is not exposed to the second principal surface 3 b. Each ofthe internal electrodes 8 is not connected to the second terminalelectrode 6.

One end of each of the internal electrodes 10 is exposed to the secondprincipal surface 3 b of the element body 3. Each of the internalelectrodes 10 is connected to the second terminal electrode 6. The otherend of each of the internal electrodes 10 is positioned in the elementbody 3, and is not exposed to the first principal surface 3 a. Each ofthe internal electrodes 10 is not connected to the first terminalelectrode 5.

Since each of the internal electrodes 7 and each of the internalelectrodes 8 are connected to the first terminal electrode 5, thepolarity of each of the internal electrodes 7 and the polarity of eachof the internal electrodes 8 are the same. Since each of the internalelectrodes 9 and each of the internal electrodes 10 are connected to thesecond terminal electrode 6, the polarity of each of the internalelectrodes 9 and the polarity of each of the internal electrodes 10 arethe same. Since the internal electrodes 7, 8 and the internal electrodes9, 10 are connected to different terminal electrodes from each other,the polarity of the internal electrodes 7, 8 and the polarity of theinternal electrodes 9, 10 are different from each other.

Each of the internal electrodes 8 is disposed to be sandwiched betweentwo internal electrodes 7. One internal electrode 8 and two internalelectrodes 7 sandwiching the one internal electrode 8 are connected tothe first terminal electrode 5, and are arranged contiguously in thesecond direction D2. These three internal electrodes 7, 8 are arrangedin the second direction D2, in the order of the internal electrode 7,the internal electrode 8, and the internal electrode 7.

Each of the internal electrodes 10 is disposed to be sandwiched betweentwo internal electrodes 9. One internal electrode 10 and two internalelectrodes 9 sandwiching the one internal electrode 10 are connected tothe second terminal electrode 6, and are arranged contiguously in thesecond direction D2. These three internal electrodes 9, 10 are arrangedin the second direction D2, in the order of the internal electrode 9,the internal electrode 10, and the internal electrode 9.

The plurality of internal electrodes 7, 8, 9, 10 is divided into aplurality of first internal electrode groups and a plurality of secondinternal electrode groups. Each of the first internal electrode groupsincludes three internal electrodes 7, 8 arranged contiguously in thesecond direction D2. Each of the second internal electrode groupsincludes three internal electrodes 9, 10 arranged contiguously in thesecond direction D2. The first internal electrode groups and the secondinternal electrode groups are positioned alternately in the seconddirection D2.

Each of the internal electrodes 7 and each of the internal electrodes 8adjacent to each other in the second direction D2 oppose each other.Each of the internal electrodes 7 and each of the internal electrodes 9adjacent to each other in the second direction D2 oppose each other.Each of the internal electrodes 9 and each of the internal electrodes 10adjacent to each other in the second direction D2 oppose each other. Aninterval between each of the internal electrodes 7 and each of theinternal electrodes 8 adjacent to each other in the second direction D2,an interval between each of the internal electrodes 7 and each of theinternal electrodes 9 adjacent to each other in the second direction D2,and an interval between each of the internal electrodes 9 and each ofthe internal electrodes 10 adjacent to each other in the seconddirection D2 are equivalent to each other. The plurality of internalelectrodes 7, 8, 9, 10 is arranged at equal intervals in the seconddirection D2. The “equivalent” does not necessarily mean only thatvalues are exactly equal to each other. Even in a case in which a slightdifference within a predetermined range or a manufacturing error isincluded in the values, the values may be regarded as being equivalentto each other. For example, in a case in which the intervals between theinternal electrodes 7, 9 adjacent to each other are included within arange of ±10% from the average value of the intervals, the intervals maybe defined as being equivalent to each other.

Each of the internal electrodes 7, 8, 9, 10 has, for example, arectangular shape in a plan view, as illustrated in FIG. 4 and FIG. 5.In each of the internal electrodes 7, 8, 9, 10, the length in the thirddirection D3 is greater than the length in the first direction D1. Eachof the internal electrodes 7, 8, 9, 10 includes a metal material (forexample, Ni or Cu) normally used as an internal electrode of an electricelement of a multilayer type. Each of the internal electrodes 7, 8, 9,10 is configured as a sintered body of a conductive paste including theabove metal material.

The element body 3 includes a plurality of first areas 20A and aplurality of second areas 20B, as illustrated in FIG. 3. Each of thefirst areas 20A is positioned between each of the internal electrodes 7and each of the internal electrodes 9 opposing each other. Since each ofthe internal electrodes 7 and each of the internal electrodes 9 opposingeach other have different polarities from each other, each of the firstareas 20A generates capacitance. Each of the second areas 20B ispositioned between a pair of internal electrodes 7 opposing each othervia each of the internal electrodes 8, and between a pair of internalelectrodes 9 opposing each other via each of the internal electrodes 10.Since each of the internal electrodes 8 and each of the internalelectrodes 7 have the same polarity, and each of the internal electrodes9 and each of the internal electrodes 10 have the same polarity, each ofthe second areas 20B does not generate capacitance.

Each of the internal electrodes 8, 10 is disposed to divide each of thesecond areas 20B. Each of the internal electrodes 8 does not contributeto generation of capacitance. Each of the internal electrodes 8 divideseach of the second areas 20B positioned between the pair of internalelectrodes 7 into two areas. Widths in the second direction D2 of thetwo areas divided by each of the internal electrodes 8 are equivalent toeach other. Each of the internal electrodes 10 does not contribute togeneration of capacitance. Each of the internal electrodes 10 divideseach of the second areas 20B positioned between the pair of internalelectrodes 9 into two areas. Widths in the second direction D2 of thetwo areas divided by each of the internal electrodes 10 are equivalentto each other. A width in the second direction D2 of each of the areasdivided by each of the internal electrodes 8 and a width in the seconddirection D2 of each of the areas divided by each of the internalelectrodes 10 are equivalent to each other.

The first areas 20A and the second areas 20B are positioned alternatelyin the second direction D2. Each of the first areas 20A is positionedbetween a pair of second areas 20B. The pair of second areas 20Bsandwiches each of the first areas 20A in the second direction D2.

As described above, in the embodiment, the first terminal electrode 5includes the first plating layer 53. For this reason, in the multilayerceramic capacitor C1, as illustrated in FIG. 9, wire bonding mounting ispossible using wire 71 including the base metal on the first principalsurface 3 a side. The wire bonding mounting using the wire 71 includingthe base metal is less expensive than the wire bonding mounting usingwire including Au. The wire 71 is, for example, wire including Al or Cu.

The second terminal electrode 6 includes the solder layer 65. For thisreason, in the multilayer ceramic capacitor C1, as illustrated in FIG.9, solder mounting is possible on the second principal surface 3 b side.

FIG. 9 is a diagram for describing mounting structure of the multilayerceramic capacitor according to the embodiment. The multilayer ceramiccapacitor C1 is electrically and physically connected to an electronicdevice ED (for example, circuit board or electronic component) by usingthe solder mounting. The multilayer ceramic capacitor C1 is electricallyconnected to the electronic device ED by using the wire bondingmounting.

The second sintered metal layer 61 includes a glass component in orderto increase bonding strength between the second sintered metal layer 61and the element body 3. In general, the glass component has poor solderwettability. For this reason, in a case in which the solder layer 65 isformed on the second sintered metal layer 61, the bonding strengthbetween the second sintered metal layer 61 and the solder layer 65 maybe decreased due to the glass component included in the second sinteredmetal layer 61. In contrast to it, in the multilayer ceramic capacitorC1, since the second terminal electrode 6 includes the second platinglayer 63, that is, the second plating layer 63 is formed on the secondsintered metal layer 61, the bonding strength between the secondelectrode structure and the solder layer 65 is improved. In a case inwhich the second plating layer 63 is a Ni plating layer, heat resistanceof the second plating layer 63 is improved, and solder corrosionresistance of the second plating layer 63 is improved.

In the embodiment, the first plating layer 53 is formed on the firstsintered metal layer 51 formed on the first principal surface 3 a, andthe second plating layer 63 is formed on the second sintered metal layer61 formed on the second principal surface 3 b. For this reason,infiltration of a plating solution into the element body 3 is suppressedby the first sintered metal layer 51, in the embodiment, in comparisonwith a multilayer ceramic capacitor including a configuration in whichthe first terminal electrode 5 does not include the first sintered metallayer 51, when the first plating layer 53 is formed. Similarly,infiltration of a plating solution into the element body 3 is suppressedby the second sintered metal layer 61, in the embodiment, in comparisonwith a multilayer ceramic capacitor including a configuration in whichthe second terminal electrode 6 does not include the second sinteredmetal layer 61, when the second plating layer 63 is formed. Theinfiltration of the plating solution may deteriorate electricalcharacteristics of the multilayer ceramic capacitor C1. Therefore, theinfiltration of the plating solution is suppressed, so thatdeterioration of the electrical characteristics of the multilayerceramic capacitor C1 is suppressed.

The first plating layer 53 is a Ni plating layer or a Cu plating layer.For this reason, the wire including Al or Cu is easily bonded to thefirst plating layer 53.

In the second electrode structure including the second sintered metallayer 61 and the second plating layer 63, the depression is formed inthe inner area when viewed from the direction perpendicular to thesecond principal surface 3 b. The solder layer 65 is formed convexly onthe depression. In the multilayer ceramic capacitor C1, an amount ofsolder configuring the solder layer 65 is greater in comparison with,for example, a multilayer ceramic capacitor including a configuration inwhich the depression is not formed in the second electrode structure.For this reason, when the multilayer ceramic capacitor C1 issolder-mounted to the electronic device ED on the second principalsurface 3 b side, generation of a void in the solder is suppressed. As aresult, the bonding strength between the multilayer ceramic capacitor C1and the electronic device ED is improved.

The metal included in the solder layer 65 and having the higher meltingpoint than the melting point of Sn is Sb. The solder layer 65 includingSb as the metal having the higher melting point than the melting pointof Sn is less expensive than the solder layer including the preciousmetal as the metal having the higher melting point than the meltingpoint of Sn. For this reason, cost down of the multilayer ceramiccapacitor C1 is possible.

The second plating layer 63 is a Ni plating layer, and there is the area67 in which the alloy of Ni and Sn exists, between the second platinglayer 63 and the solder layer 65. As a result, the bonding strengthbetween the second plating layer 63 and the solder layer 65 is improved.

In the embodiment, the peripheral portion of the area 67 is exposed fromthe solder layer 65. The peripheral portion of the area 67 is positionedto surround the solder layer 65, when viewed from the directionperpendicular to the second principal surface 3 b. The area 67 in whichthe alloy of Ni and Sn exists has low solder wettability. For thisreason, spillage is suppressed of the solder configuring the solderlayer 65 from the depression formed on the second electrode structure.

The first sintered metal layer 51 and the second sintered metal layer 61include the base metal. The first sintered metal layer 51 and the secondsintered metal layer 61 are less expensive than the sintered metal layerincluding a metal other than the base metal (for example, preciousmetal). For this reason, cost down of the multilayer ceramic capacitorC1 is possible. Since the first sintered metal layer 51 and the firstplating layer 53 include the base metal, adhesion between the firstsintered metal layer 51 and the first plating layer 53 is improved.Since the second sintered metal layer 61 and the second plating layer 63include the base metal, adhesion between the second sintered metal layer61 and the second plating layer 63 is improved.

A hole may be formed in the first sintered metal layer 51 and the secondsintered metal layer 61. In a case in which the hole is formed in thefirst sintered metal layer 51 and the second sintered metal layer 61,moisture infiltrates from the hole, and may influence the electricalcharacteristics of the multilayer ceramic capacitor C1. In theembodiment, since the first terminal electrode 5 includes the firstplating layer 53, the hole is closed by the first plating layer 53 evenin a case in which the hole is formed in the first sintered metal layer51. Therefore, infiltration is suppressed of the moisture and the likefrom the hole formed in the first sintered metal layer 51. Since thesecond terminal electrode 6 includes the second plating layer 63, thehole is closed by the second plating layer 63 even in a case in whichthe hole is formed on the second sintered metal layer 62. Therefore,infiltration is reliably prevented of the moisture and the like from thehole formed in the second sintered metal layer 61. Thus, moistureresistance of the multilayer ceramic capacitor C1 is improved, anddeterioration of the electrical characteristics of the multilayerceramic capacitor C1 is reliably prevented.

The multilayer ceramic capacitor C1 includes the plurality of internalelectrodes 7, 8, 9, 10 arranged at equal intervals in the seconddirection D2 to oppose each other, inside the element body 3. Theplurality of internal electrodes 7 is connected to the first terminalelectrode 5, and is not connected to the second terminal electrode 6.The plurality of internal electrodes 9 is connected to the secondterminal electrode 6, and is not connected to the first terminalelectrode 5. The plurality of internal electrodes 8 is not connected toat least the second terminal electrode 6. The plurality of internalelectrodes 10 is not connected to at least the first terminal electrode5. The element body 3 includes the plurality of first areas 20A and theplurality of second areas 20B. Each of the first areas 20A is positionedbetween each of the internal electrodes 7 and each of the internalelectrodes 9 opposing each other. Each of the second areas 20B ispositioned between the pair of internal electrodes 7 opposing each othervia each of the internal electrodes 8, and between the pair of internalelectrodes 9 opposing each other via each of the internal electrodes 10.The first areas 20A and the second areas 20B are positioned alternatelyin the second direction D2.

The internal electrodes 7 connected to the first terminal electrode 5and the internal electrodes 9 connected to the second terminal electrode6 have different polarities from each other. Each of the first areas 20Apositioned between the internal electrodes 7, 9 opposing each othergenerates capacitance. The internal electrodes 7 have the same polarityto each other. The internal electrodes 8 not connected to the secondterminal electrode 6 do not have a different polarity from a polarity ofthe internal electrodes 7 at least. The internal electrodes 9 have thesame polarity to each other. The internal electrodes 10 not connected tothe first terminal electrode 5 do not have a different polarity from apolarity of the internal electrodes 9 at least. Therefore, each of thesecond areas 20B positioned between the pair of internal electrodes 7opposing each other via each of the internal electrodes 8, and each ofthe second areas 20B formed between the pair of internal electrodes 9opposing each other via the internal electrodes 10 do not generatecapacitance.

The element body 3 includes the inner layer portion 11 (internalelectrode disposition area) in which the plurality of internalelectrodes 7, 8, 9, 10 is disposed, and the pair of outer layer portions12 (internal electrode non-disposition area) in which the plurality ofinternal electrodes 7, 8, 9, 10 is not disposed. The pair of outer layerportions 12 sandwiches the inner layer portion 11 in the seconddirection D2. The inner layer portion 11 includes the plurality of firstareas 20A that generates capacitance, and the plurality of second areas20B that does not generate capacitance. In the multilayer ceramiccapacitor C1, a desired capacitance is secured by the plurality of firstareas 20A.

The second areas 20B that does not generate capacitance is included inthe inner layer portion 11. For this reason, in the multilayer ceramiccapacitor C1, the inner layer portion 11 is wider and the outer layerportions 12 is narrower, in comparison with, for example, the followingmultilayer ceramic capacitor to be compared. In the multilayer ceramiccapacitor to be compared, the internal electrodes having differentpolarities are disposed alternately. The size of the element body of themultilayer ceramic capacitor to be compared is the same as the size ofthe element body of the multilayer ceramic capacitor C1, and thecapacitance of the multilayer ceramic capacitor to be compared is thesame as the capacitance of the multilayer ceramic capacitor C1.

In the multilayer ceramic capacitor C1, the element body 3 is configuredas a sintered body of a dielectric ceramic material, and each of theinternal electrodes 7, 8, 9, 10 is configured as a sintered body of ametal material. A degree of sintering of the dielectric ceramic materialin the inner layer portion 11 and a degree of sintering of thedielectric ceramic material in the outer layer portions 12 are differentfrom each other due to presence/absence of the metal material to be theinternal electrodes 7, 8, 9, 10. For example, the degree of sintering ofthe dielectric ceramic material in the outer layer portions 12 is lowerthan the degree of sintering of the dielectric ceramic material in theinner layer portion 11. In a case in which the degree of sintering ofthe dielectric ceramic material in the inner layer portion 11 and thedegree of sintering of the dielectric ceramic material in the outerlayer portions 12 are different from each other, a crack may begenerated in the element body 3.

In the inner layer portion 11, all internal electrodes 7, 8, 9, 10 arearranged at equal intervals in the second direction D2. For this reason,in the inner layer portion 11, the degree of sintering of the dielectricceramic is substantially uniform. In the multilayer ceramic capacitorC1, the inner layer portion 11 is wider than that of the abovemultilayer ceramic capacitor to be compared, that is, the area is widerin which the degree of sintering of the dielectric ceramic issubstantially uniform. For this reason, the degree of sintering of thedielectric ceramic in the entire of the element body 3 is stabilized. Asa result, in the multilayer ceramic capacitor C1, generation of thecrack in the element body 3 is suppressed.

In a case in which voltage is applied to the multilayer ceramiccapacitor C1, mechanical strain of a size depending on the appliedvoltage is generated due to electrostrictive effect in the element body.Since stress is generated in the element body 3 by the mechanical straindue to the electrostrictive effect, a crack may be generated in theelement body 3.

In the multilayer ceramic capacitor C1, the mechanical strain due to theelectrostrictive effect is generated in the first areas 20A; however,the mechanical strain due to the electrostrictive effect is notgenerated in the second areas 20B. The first areas 20A and the secondareas 20B are positioned alternately in the second direction D2. Forthis reason, in the multilayer ceramic capacitor C1, in comparison withthe multilayer ceramic capacitor including a configuration in which theinner layer portion 11 does not include the second areas 20B, the areasin which the mechanical strain due to the electrostrictive effect isgenerated are distributed in the inner layer portion 11. Thus, sinceconcentration of the stress is suppressed that is generated by themechanical strain due to the electrostrictive effect, generation of thecrack in the element body 3 is suppressed.

From these things, in the multilayer ceramic capacitor C1, generation ofthe crack is suppressed while the desired capacitance is secured.

In the embodiment, each of the internal electrodes 8 does not have to beconnected to the first terminal electrode 5. Each of the internalelectrodes 10 does not have to be connected to the second terminalelectrode 6. Each of the internal electrodes 8, 10 does not have to beconnected to the first terminal electrode 5 and the second terminalelectrode 6.

In the embodiment, the number of the internal electrodes 7, 8 includedin, each of the first internal electrode groups may be “four” orgreater. The number of the internal electrodes 9, 10 included in each ofthe second internal electrode groups may be “four” or greater.

Next, a configuration is described of a multilayer ceramic capacitor C2according to a modification example of the embodiment, with reference toFIG. 10 and FIG. 11. FIG. 10 and FIG. 11 are diagrams for describing across-sectional configuration of the multilayer ceramic capacitoraccording to the present modification example.

The multilayer ceramic capacitor C2 includes an element body 3, a firstterminal electrode 5 and a second terminal electrode 6, and a pluralityof internal electrodes 7, 9.

An inner layer portion 11 of the element body 3 includes an innerportion 11A, and a pair of outer portions 11B. The pair of outerportions 11B is positioned to sandwich the inner portion 11A in thesecond direction D2.

A plurality of internal electrodes 7, 8, 9, 10 is divided into aplurality of internal electrode groups 31, 32 and a plurality ofinternal electrode groups 33, 34. The plurality of internal electrodegroups 31, 32 is positioned in the outer portions 11B of the elementbody 3. The plurality of internal electrode groups 33, 34 is positionedin the inner portion 11A of the element body 3.

Each of the first internal electrode groups includes three internalelectrodes 7, 8 arranged contiguously in the second direction D2. Eachof the second internal electrode groups includes three internalelectrodes 9, 10 arranged contiguously in the second direction D2. Thefirst internal electrode groups and the second internal electrode groupsare positioned alternately in the second direction D2.

Each of the internal electrodes 7 and each of the internal electrodes 8adjacent to each other in the second direction D2 oppose each other.Each of the internal electrodes 7 and each of the internal electrodes 9adjacent to each other in the second direction D2 oppose each other.Each of the internal electrodes 9 and each of the internal electrodes 10adjacent to each other in the second direction D2 oppose each other. Aninterval between each of the internal electrodes 7 and each of theinternal electrodes 8 adjacent to each other in the second direction D2,an interval between each of the internal electrodes 7 and each of theinternal electrodes 9 adjacent to each other in the second direction D2,and an interval between each of the internal electrodes 9 and each ofthe internal electrodes 10 adjacent to each other in the seconddirection D2 are equivalent to each other. The plurality of internalelectrodes 7, 8, 9, 10 is arranged at equal intervals in the seconddirection D2.

Each of the internal electrode groups 31 includes three internalelectrodes 7, 8 arranged contiguously in the second direction D2. Eachof the internal electrodes 7 and each of the internal electrodes 8adjacent to each other in the second direction D2 oppose each other, ineach of the internal electrode groups 31.

Each of the internal electrode groups 32 includes three internalelectrodes 9, 10 arranged contiguously in the second direction D2. Eachof the internal electrodes 9 and each of the internal electrodes 10adjacent to each other in the second direction D2 oppose each other, ineach of the internal electrode groups 32.

Each of the internal electrode groups 33 includes a pair of internalelectrodes 7 arranged contiguously in the second direction D2. The pairof internal electrodes 7 adjacent to each other in the second directionD2 oppose each other, in each of the internal electrode groups 33.

Each of the internal electrode groups 34 includes a pair of internalelectrodes 9 arranged contiguously in the second direction D2. The pairof internal electrodes 9 adjacent to each other in the second directionD2 oppose each other, in each of the internal electrode groups 34.

One end of each of the internal electrodes 7, 8 included in each of theinternal electrode groups 31, 33 is exposed to a first principal surface3 a of the element body 3. Each of the internal electrodes 7, 8 isconnected to the first terminal electrode 5. The other end of each ofthe internal electrodes 7, 8 is positioned in the element body 3, and isnot exposed to a second principal surface 3 b. The internal electrodes7, 8 are not connected to the second terminal electrode 6.

One end of each of the internal electrodes 9, 10 included in each of theinternal electrode groups 32, 34 is exposed to the second principalsurface 3 b of the element body 3. Each of the internal electrodes 9, 10is connected to the second terminal electrode 6. The other end of eachof the internal electrode 9, 10 is positioned in the element body 3, andis not exposed to the second principal surface 3 b. The internalelectrodes 9, 10 are not connected to the first terminal electrode 5.

The internal electrode groups 31 and the internal electrode groups 32are arranged alternately in the second direction D2. One internalelectrode 7 of the pair of internal electrodes 7 included in each of theinternal electrode groups 31 and one internal electrode 9 of the pair ofinternal electrodes 9 included in each of the internal electrode groups32 oppose each other in the second direction D2. Since the internalelectrodes 7 and the internal electrodes 9 are connected to differentterminal electrodes from each other, the polarity of the internalelectrodes 7 and the polarity of the internal electrodes 9 are differentfrom each other. Therefore, each of first areas 20A that generatescapacitance is positioned between each of the internal electrodes 7 andeach of the internal electrodes 9 opposing each other.

Since the three internal electrodes 7, 8 included in each of theinternal electrode groups 31 are connected to the first terminalelectrode 5, the polarities of the three internal electrodes 7, 8 arethe same. Therefore, each of second areas 20B that does not generatecapacitance is positioned between the pair of internal electrodes 7, ineach of the internal electrode groups 31. Each of the second areas 20Bis positioned in the outer portions 11B.

Since the three internal electrodes 9, 10 included in each of theinternal electrode groups 32 are connected to the second terminalelectrode 6, the polarities of the three internal electrodes 9, 10 arethe same. Therefore, each of second areas 20B that does not generatecapacitance is positioned between the pair of internal electrodes 9,also in each of the internal electrode groups 32. Each of these secondareas 20B is also positioned in the outer portions 11B.

The internal electrode groups 33 and the internal electrode groups 34are arranged alternately in the second direction D2. One internalelectrode 7 of the pair of internal electrodes 7 included in each of theinternal electrode groups 33 and one internal electrode 9 of the pair ofinternal electrodes 9 included in each of the internal electrode groups34 oppose each other in the second direction D2. Since the polarity ofthe internal electrodes 7 and the polarity of the internal electrodes 9are different from each other, each of first areas 20A that generatescapacitance is positioned between each of the internal electrodes 7 andeach of the internal electrodes 9 opposing each other.

Since the pair of internal electrodes 7 included in each of the internalelectrode groups 33 is connected to the first terminal electrode 5, thepolarities of the pair of internal electrodes 7 are the same. Therefore,each of second areas 20B that does not generate capacitance ispositioned between the pair of internal electrodes 7, also in each ofthe internal electrode groups 33. Each of these second areas 20B ispositioned in the inner portion 11A.

Since the pair of internal electrodes 9 included in each of the internalelectrode groups 34 is connected to the second terminal electrode 6, thepolarities of the pair of internal electrodes 9 are the same. Therefore,each of second areas 20B that does not generate capacitance ispositioned between the pair of internal electrodes 9, also in each ofthe internal electrode groups 34. Each of these second areas 20B is alsopositioned in the inner portion 11A.

An interval between the pair of internal electrodes 7 adjacent to eachother in the second direction D2, an interval between the pair ofinternal electrodes 9 adjacent to each other in the second direction D2,an interval between each of the internal electrodes 7 and each of theinternal electrodes 8 adjacent to each other in the second direction D2,an interval between each of the internal electrodes 7 and each of theinternal electrodes 9 adjacent to each other in the second direction D2,and an interval between each of the internal electrodes 9 and each ofthe internal electrodes 10 adjacent to each other in the seconddirection D2 are equivalent to each other. That is, the plurality ofinternal electrodes 7, 8, 9, 10 is arranged at equal intervals in thesecond direction D2.

The first areas 20A and the second areas 20B are positioned alternatelyin the second direction D2. Each of the first areas 20A is positionedbetween a pair of second areas 20B. That is, the pair of second areas20B sandwiches each of the first areas 20A in the second direction D2.

A width in the second direction D2 of each of the second areas 20Bpositioned between the pair of internal electrodes 7 included in each ofthe internal electrode groups 31 is greater than a width in the seconddirection D2 of each of the second areas 20B positioned between the pairof internal electrodes 7 included in each of the internal electrodegroups 33. A width in the second direction D2 of each of the secondareas 20B positioned between the pair of internal electrodes 9 includedin each of the internal electrode groups 32 is greater than a width inthe second direction D2 of each of the second areas 20B positionedbetween the pair of internal electrodes 9 included in each of theinternal electrode groups 34. The width in the second direction D2 ofeach of the second areas 20B positioned between the pair of internalelectrodes 7 included in each of the internal electrode groups 31 andthe width in the second direction D2 of each of the second areas 20Bpositioned between the pair of internal electrodes 9 included in each ofthe internal electrode groups 32 are equivalent to each other. A widthin the second direction D2 of each of the first areas 20A positionedbetween one internal electrode 7 included in each of the internalelectrode groups 31 and one internal electrode 9 included in each of theinternal electrode groups 32, a width in the second direction D2 of eachof the first areas 20A positioned between one internal electrode 7included in each of the internal electrode groups 33 and one internalelectrode 9 included in each of the internal electrode groups 34, thewidth in the second direction D2 of each of the second areas 20Bpositioned between the pair of internal electrodes 7 included in each ofthe internal electrode groups 33, and the width in the second directionD2 of each of the second areas 20B positioned between the pair ofinternal electrodes 9 included in each of the internal electrode groups34 are equivalent to each other.

As described above, in the present modification example, the pluralityof internal electrode groups 31 and the plurality of internal electrodegroups 32 are arranged alternately in the second direction D2. Oneinternal electrode 7 of the three internal electrodes 7, 8 included ineach of the internal electrode groups 31 and one internal electrode 9 ofthe three internal electrodes 9, 10 included in each of the internalelectrode groups 32 oppose each other in the second direction D2. As aresult, the plurality of first areas 20A that generates capacitance isdisposed in each of the outer portions 11B of the element body 3.

Since the three internal electrodes 7, 8 included in each of theinternal electrode groups 31 all have the same polarity, each of thesecond areas 20B positioned between the pair of internal electrodes 7respectively positioned at both ends in the second direction D2 of thethree internal electrodes 7, 8 does not generate capacitance. Since thethree internal electrodes 9, 10 included in each of the internalelectrode groups 32 all have the same polarity, each of the second areas20B positioned between the pair of internal electrodes 9 respectivelypositioned at both ends in the second direction D2 of the three internalelectrodes 9, 10 does not generates capacitance either. Therefore, ineach of the outer portions 11B of the element body 3, the first areas20A that generate capacitance and the second areas 20B that do notgenerate capacitance are positioned alternately in the second directionD2.

The plurality of internal electrode groups 33 and the plurality ofinternal electrode groups 34 are arranged alternately in the seconddirection D2. One internal electrode 7 of the pair of internalelectrodes 7 included in each of the internal electrode groups 33 andone internal electrode 9 of the pair of internal electrodes 9 includedin each of the internal electrode groups 34 oppose each other in thesecond direction D2. As a result, the plurality of first areas 20A thatgenerates capacitance is disposed in the inner portion 11A of theelement body 3.

Since the pair of internal electrodes 7 included in each of the internalelectrode groups 33 has the same polarity, each of the second areas 20Bpositioned between the pair of internal electrodes 7 does not generatecapacitance, in each of the internal electrode groups 33. Since the pairof internal electrodes 9 included in each of the internal electrodegroups 34 has the same polarity, each of the second areas 20B positionedbetween the pair of internal electrodes 9 does not generate capacitance,in each of the internal electrode groups 34. Therefore, also in theinner portion 11A of the element body 3, the first areas 20A thatgenerates capacitance and the second areas 20B that do not generatecapacitance are positioned alternately in the second direction D2.

The element body 3 includes the inner layer portion 11 in which theplurality of internal electrode groups 31, 32, 33, 34 is disposed, and apair of outer layer portions 12 in which the plurality of internalelectrode groups 31, 32, 33, 34 is not disposed. The pair of outer layerportions 12 sandwiches the inner layer portion 11 in the seconddirection D2. The inner layer portion 11 includes the plurality of firstareas 20A that generates capacitance, and the plurality of second areas20B that does not generate capacitance. Also in the multilayer ceramiccapacitor C2, a desired capacitance is secured by the plurality of firstareas 20A.

The second areas 20B that do not generate capacitance are included inthe inner layer portion 11. For this reason, also in the multilayerceramic capacitor C2, the inner layer portion 11 is wider, and the outerlayer portions 12 are narrower, in comparison with, for example, thefollowing multilayer ceramic capacitor to be compared. In the multilayerceramic capacitor to be compared, the internal electrodes havingdifferent polarities are disposed alternately. The size of the elementbody of the multilayer ceramic capacitor to be compared is the same asthe size of the element body of the multilayer ceramic capacitor C2, andthe capacitance of the multilayer ceramic capacitor to be compared isthe same as the capacitance of the multilayer ceramic capacitor C2.

In the inner layer portion 11, all internal electrodes 7, 8, 9, 10 arearranged at equal intervals in the second direction D2. For this reason,in the inner layer portion 11, the degree of sintering of the dielectricceramic is substantially uniform. In the multilayer ceramic capacitorC2, the inner layer portion 11 is wider than that of the abovemultilayer ceramic capacitor to be compared, that is, the area is widerin which the degree of sintering of the dielectric ceramic issubstantially uniform. For this reason, the degree of sintering of thedielectric ceramic in the entire of the element body 3 is stabilized. Asa result, also in the multilayer ceramic capacitor C2, generation of thecrack in the element body 3 is suppressed.

From these things, also in the multilayer ceramic capacitor C2,generation of the crack is suppressed while the desired capacitance issecured.

In the present modification example, the number of internal electrodes7, 8, 9, 10 is “three” that are included in each of the internalelectrode groups 31, 32 positioned in the outer portions 11B of theelement body 3, and the number of internal electrodes 7, 9 is “two” thatare included in each of the internal electrode groups 33, 34 positionedin the inner portion 11A of the element body 3. The number of internalelectrodes 7, 8, 9, 10 included in each of the internal electrode groups31, 32 positioned in the outer portions 11B is greater than the numberof internal electrodes 7, 9 included in each of the internal electrodegroups 33, 34 positioned in the inner portion 11A. Therefore, in a casein which a crack is generated in the outer portions 11B of the elementbody 3, the crack hardly reaches the internal electrodes 7, 9 that havedifferent polarities from each other and contribute capacitance.

In the present modification example, the number of internal electrodes7, 8, 9, 10 included in each of the internal electrode groups 31, 32 maybe “four” or greater. The number of internal electrodes 7, 9 included ineach of the internal electrode groups 33, 34 may be “three” or greater.

The embodiment of the present invention has been described above;however, the present invention is not necessarily limited to theembodiment described above, and can be variously modified withoutdeparting from the gist thereof.

In the embodiment and the modification example, the multilayer ceramiccapacitors C1, C2 have been described as examples of the electroniccomponent; however, the application range of the present invention isnot limited to the multilayer ceramic capacitor. The present inventioncan also be applied to a multilayer electronic component such as amultilayer inductor, a multilayer varistor, a multilayer piezoelectricactuator, a multilayer thermistor, or a multilayer composite component,or an electronic component other than the multilayer electroniccomponent.

What is claimed is:
 1. An electronic component comprising: an elementbody having a first principal surface and a second principal surfaceopposing each other in a first direction; a first terminal electrodedisposed on the first principal surface side of the element body; and asecond terminal electrode disposed on the second principal surface sideof the element body, wherein: the first terminal electrode includes: afirst sintered metal layer formed on the first principal surface; and afirst plating layer formed on the first sintered metal layer andincluding a first base metal; the second terminal electrode includes: asecond sintered metal layer formed on the second principal surface; asecond plating layer formed on the second sintered metal layer andincluding a second base metal; and a solder layer formed on the secondplating layer and including Sn and a metal having a higher melting pointthan the melting point of Sn; the second base metal can be the same asor different from the first base metal; and the first plating layerconsists of a Ni plating layer that is an outermost layer of the firstterminal electrode.
 2. The electronic component according to claim 1,wherein the metal having a higher melting point than the melting pointof Sn is Sb.
 3. The electronic component according to claim 1, furthercomprising a plurality of internal electrodes arranged at equalintervals in a second direction perpendicular to the first direction tooppose each other, inside the element body, wherein the plurality ofinternal electrodes includes: a plurality of first internal electrodesconnected to the first terminal electrode and not connected to thesecond terminal electrode; a plurality of second internal electrodesconnected to the second terminal electrode and not connected to thefirst terminal electrode; a plurality of third internal electrodes notconnected to at least the second terminal electrode; and a plurality offourth internal electrodes not connected to at least the first terminalelectrode, and the element body includes: a plurality of first areaseach of which is positioned between each of the first internalelectrodes and each of the second internal electrodes opposing eachother; and a plurality of second areas each of which is positionedbetween the first internal electrodes opposing each other via each ofthe third internal electrodes and between the second internal electrodesopposing each other via each of the fourth internal electrodes, and eachof the first areas and each of the second areas are positionedalternately in the second direction.
 4. The electronic componentaccording to claim 1, further comprising: a plurality of first internalelectrode groups including a first number of the first internalelectrodes connected to the first terminal electrode and arranged in thesecond direction perpendicular to the first direction inside the elementbody; a plurality of second internal electrode groups including thefirst number of the second internal electrodes connected to the secondterminal electrode and arranged in the second direction inside theelement body; a plurality of third internal electrode groups including asecond number of the first internal electrodes connected to the firstterminal electrode and arranged in the second direction inside theelement body; and a plurality of fourth internal electrode groupsincluding the second number of the second internal electrodes connectedto the second terminal electrode and arranged in the second directioninside the element body, wherein the first number and the second numberare integers of two or greater that are different from each other, theelement body includes an inner portion, and a pair of outer portionspositioned to sandwich the inner portion in the second direction, aninterval in the second direction between the first internal electrodesincluded in each of the first internal electrode groups, an interval inthe second direction between the second internal electrodes included ineach of the second internal electrode groups, an interval in the seconddirection between each of the first internal electrodes included in eachof the first internal electrode groups and each of the second internalelectrodes included in each of the second internal electrode groups, aninterval in the second direction between the first internal electrodesincluded in each of the third internal electrode groups, an interval inthe second direction between the second internal electrodes included ineach of the fourth internal electrode groups, and an interval in thesecond direction between each of the first internal electrodes includedin each of the third internal electrode groups and each of the secondinternal electrodes included in each of the fourth internal electrodegroups are equivalent to each other, each of the first internalelectrode groups and each of the second internal electrode groups arepositioned in the pair of outer portions, and are arranged alternatelyin the second direction in such a manner that one first internalelectrode of the first number of the first internal electrodes includedin each of the first internal electrode groups and one second internalelectrode of the first number of the second internal electrodes includedin each of the second internal electrode groups oppose each other in thesecond direction, each of the third internal electrode groups and eachof the fourth internal electrode groups are positioned in the innerportion, and are arranged alternately in the second direction in such amanner that one first internal electrode of the second number of thefirst internal electrodes included in each of the third internalelectrode groups and one second internal electrode of the second numberof the second internal electrodes included in each of the fourthinternal electrode groups oppose each other in the second direction. 5.An electronic component comprising: an element body having a firstprincipal surface and a second principal surface opposing each other ina first direction; a first terminal electrode disposed on the firstprincipal surface side of the element body; and a second terminalelectrode disposed on the second principal surface side of the elementbody, wherein: the first terminal electrode includes: a first sinteredmetal layer formed on the first principal surface; and a first platinglayer formed on the first sintered metal layer and including a firstbase metal; the second terminal electrode includes: a second sinteredmetal layer formed on the second principal surface; a second platinglayer formed on the second sintered metal layer and including a secondbase metal; and a solder layer formed on the second plating layer andincluding Sn and a metal having a higher melting point than the meltingpoint of Sn; the second base metal can be the same as or different fromthe first base metal; a depression is formed in an inner area whenviewed from a direction perpendicular to the second principal surface,on an electrode structure including the second sintered metal layer andthe second plating layer, and the solder layer is formed convexly on thedepression.
 6. An electronic component comprising: an element bodyhaving a first principal surface and a second principal surface opposingeach other in a first direction; a first terminal electrode disposed onthe first principal surface side of the element body; and a secondterminal electrode disposed on the second principal surface side of theelement body, wherein: the first terminal electrode includes: a firstsintered metal layer formed on the first principal surface; and a firstplating layer formed on the first sintered metal layer and including afirst base metal; the second terminal electrode includes: a secondsintered metal layer formed on the second principal surface; a secondplating layer formed on the second sintered metal layer and including asecond base metal; and a solder layer formed on the second plating layerand including Sn and a metal having a higher melting point than themelting point of Sn; the second base metal can be the same as ordifferent from the first base metal; the second plating layer is a Niplating layer, and there is an area in which an alloy of Ni and Snexists, between the second plating layer and the solder layer.
 7. Anelectronic component comprising: an element body having a firstprincipal surface and a second principal surface opposing each other ina first direction; a first terminal electrode disposed on the firstprincipal surface side of the element body; a second terminal electrodedisposed on the second principal surface side of the element body; aplurality of first internal electrode groups including a first number ofthe first internal electrodes connected to the first terminal electrodeand arranged in the second direction perpendicular to the firstdirection inside the element body; a plurality of second internalelectrode groups including the first number of the second internalelectrodes connected to the second terminal electrode and arranged inthe second direction inside the element body; a plurality of thirdinternal electrode groups including a second number of the firstinternal electrodes connected to the first terminal electrode andarranged in the second direction inside the element body; and aplurality of fourth internal electrode groups including the secondnumber of the second internal electrodes connected to the secondterminal electrode and arranged in the second direction inside theelement body; wherein: the first terminal electrode includes: a firstsintered metal layer formed on the first principal surface; and a firstplating layer formed on the first sintered metal layer and including afirst base metal; the second terminal electrode includes: a secondsintered metal layer formed on the second principal surface; a secondplating layer formed on the second sintered metal layer and including asecond base metal; and a solder layer formed on the second plating layerand including Sn and a metal having a higher melting point than themelting point of Sn; the second base metal can be the same as ordifferent from the first base metal; the first number and the secondnumber are integers of two or greater that are different from eachother; the element body includes an inner portion, and a pair of outerportions positioned to sandwich the inner portion in the seconddirection; an interval in the second direction between the firstinternal electrodes included in each of the first internal electrodegroups, an interval in the second direction between the second internalelectrodes included in each of the second internal electrode groups, aninterval in the second direction between each of the first internalelectrodes included in each of the first internal electrode groups andeach of the second internal electrodes included in each of the secondinternal electrode groups, an interval in the second direction betweenthe first internal electrodes included in each of the third internalelectrode groups, an interval in the second direction between the secondinternal electrodes included in each of the fourth internal electrodegroups, and an interval in the second direction between each of thefirst internal electrodes included in each of the third internalelectrode groups and each of the second internal electrodes included ineach of the fourth internal electrode groups are equivalent to eachother; each of the first internal electrode groups and each of thesecond internal electrode groups are positioned in the pair of outerportions, and are arranged alternately in the second direction in such amanner that one first internal electrode of the first number of thefirst internal electrodes included in each of the first internalelectrode groups and one second internal electrode of the first numberof the second internal electrodes included in each of the secondinternal electrode groups oppose each other in the second direction;each of the third internal electrode groups and each of the fourthinternal electrode groups are positioned in the inner portion, and arearranged alternately in the second direction in such a manner that onefirst internal electrode of the second number of the first internalelectrodes included in each of the third internal electrode groups andone second internal electrode of the second number of the secondinternal electrodes included in each of the fourth internal electrodegroups oppose each other in the second direction; and the first numberis greater than the second number.